The Irish Draught Sport Horse (or the Irish Sport Horse, depending on if you're in North America or Europe), had traditionally been a cross between the Irish Draught and the Thoroughbred. Not yet considered its own breed, despite the fact that it is often bred from parents that are both Irish Draught Sport Horses as well as purebred crosses, these popular horses can be registered through the Irish Draught studbooks in both North America and in the horse's native Ireland. Vastly popular and selling for high prices in both Europe and America, the Irish Draught Sport Horse has seen so much success in various competitions that the Irish Sport Horse Studbook has been the leading studbook in the World Breeding Federation for Sport Horses Eventing Rankings for the thirteenth consecutive year in 2006/2007.

The Irish Sport Horse has seen international success in events such as cross country, show jumping and eventing, and the horse is even considered an excellent mount for novice riders, thanks to its balance and intelligence. The horse has retained the best of both worlds in the traditional mix of Irish Draught and Thoroughbred, usually inheriting the power and even temperament of the former and the athleticism and speed of the latter. While there are other breeds being brought into the mix with good results, such as Arabians, Warmbloods and Quarter Horses, it is the Irish Draught / Thoroughbred cross that has brought the Irish Sport Horse its international success.

There are slight differences in the names of the horse, whether it is found in North America or in Europe, but there is more to the differences than just the name. According to the Irish Draught Horse Society of North America, the horse, called the Irish Draught Sport Horse there, must have a portion of Registered Irish Draught blood in its pedigree in order to be called an Irish Draught Sport Horse. They also claim that those horses that can be registered by the Irish Horse Board, which controls the original Irish Sport Horse Studbook, do not necessarily have to have Irish Draught Horse blood in their pedigree. According to the Irish Horse Board, there are several sections that are available to those horses that are eligible to be registered, including a supplementary section for those horses with no or partial pedigrees. In any case, all horses must reach either a minimum of accepted pedigree or success in performance before they can be registered.

Because the horse can now be crossed with several different breeds, the Irish Sport Horse can come in varied colors and sizes. The horse tends to fall in three different categories: a lightweight which can carry a rider up to 150 pounds, a middleweight that can carry up to 195 pounds, and heavyweight which can carry those 195 pounds or heavier. Today, the majority of Irish Sport Horses are middleweights, as it is uncommon to find Irish Sport Horses that can be considered either lightweights or heavyweights. The horse can range anywhere from fifteen to seventeen hands.